During dental procedures it is common for dentists or other medical professionals working in the oral cavity to make use of a mirror. The mirror is usually mounted on a handle with the plane of the mirror being at an angle to the handle. The mirror is used at the same time as other dental instruments, to facilitate viewing or illumination of the work site.
While conducting appropriate medical procedures at a work site, it is often the case that various substances may fall on the reflective surface of the mirror. This may include bodily fluids originating in the cavity being worked on, cooling fluids originating from a dental hand piece or other medical instrument or other debris which maybe generated at the worksite such as cleaning grit, material removed from a tooth or bone and the like. This material generated at the worksite is often deposited on some portion of the mirror. Debris, which may be either solid or liquid, eventually blocks the operator's vision and forces the operator to frequently clean the mirror surface either by wiping it off or by having another person assisting during the medical procedures, apply fluid onto the mirror. Both of these procedures are frustrating and objectional to the medical professional.
This problem has been well recognized in the past and various attempts have been made to provide mirrors for such use which can be cleaned by various methods. In some cases the handle portion of the mirror is fitted with a suction conduit that is intended to draw debris deposited on the mirror surface, into the handle away from the mirror surface. In other cases, surfactants and anti-fogging solutions have been applied over the surface of the mirror but these are seldom suitable for handling appreciable volumes of liquids such as cooling water associated with a dental hand piece. Various forms of rinsing jets applying either water or air to the surface of the mirror have also been proposed. In some cases a brush, wiper or other cleaning surface have been included in the mirror and the brush or wiper is cycled from time to time to remove debris from the mirror.
In addition to the aforementioned approaches which have been developed to deal with this problem, another proposal is to dispel debris, whether solid or liquid, by means of centrifugal forces. This is accomplished by rotating the reflective surface so that any debris or liquid which may fall on the surface is flung from the mirror surface. In order to cause the mirror surface to rotate, it has been suggested to use some form of air turbine driven motor. An example is shown in U.S. Pat. No. 6,247,924 issued Jun. 19, 2001. This patent discloses a mirror which includes turbine blades. The turbine blades are attached to the bottom of the mirror surface and the handle is attached to a suction device which draws air into the mirror housing, past the edges of the mirror surface. The turbine blades rotate and cause the mirror surface to rotate so as to promote removal of water and other foreign substances.
Mirrors used for medical/dental purposes must be suitably disinfected before reuse on a succeeding patient. The heat and/or chemicals involved in disinfection tend to shorten the life of the mechanical features included for debris removal. Additionally, the reflective surface is subject to abrasion from the constant deposition and removal of debris and accordingly, the useful life of reflective surface is relatively short in most cases, even shorter than the mechanical components referred to above. Accordingly, all of these prior techniques have some applicability, there remains a need for alternate solutions for keeping the mirror clean using a structure with acceptable life span.
A second problem which is often associated with the use of such mirrors within cavities, arises from the need to direct light to a desired area within the cavity. In most dental suites, there is an overhead light which can be directed into the patient's oral cavity. However, a mirror is frequently used to direct the light much more precisely to a worksite which may not be illuminated directly by an overhead light. Dentists thus often use their mirror to reflect the light coming from the overhead light onto the operating site. It would be desirable that there be additional light which can be selectively directed on the reflective surface of the mirror to be reflected onto an operating site or to otherwise provide additional illumination of an operating site.
Another requirement for such devices is to enable the dentist to direct light where desired while at the same time not reflecting light back from the mirror directly into the dentist's eyes. The problem may be exacerbated as the mirror is often deployed at different angles depending upon whether the dentist is working on the upper dental arch or the lower dental arch and whether the dentist is working on the patient's right side or left side of the oral cavity.